81866327 has 2 divisors, whose sum is σ = 81866328. Its totient is φ = 81866326.

The previous prime is 81866321. The next prime is 81866329. The reversal of 81866327 is 72366818.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81866327 - 2⁶ = 81866263 is a prime.

Together with 81866329, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81866321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40933163 + 40933164.

It is an arithmetic number, because the mean of its divisors is an integer number (40933164).

Almost surely, 2^81866327 is an apocalyptic number.

81866327 is a deficient number, since it is larger than the sum of its proper divisors (1).

81866327 is an equidigital number, since it uses as much as digits as its factorization.

81866327 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 41.

The square root of 81866327 is about 9048.0012709990. The cubic root of 81866327 is about 434.2119470623.

The spelling of 81866327 in words is "eighty-one million, eight hundred sixty-six thousand, three hundred twenty-seven".